Flowing device, tubing, and casing flow



March 30, 1943. BQYYNTON I 2,314,868

FLOWING DEVICE, TUBING, AND CASING FLOW Filed Dec. 8, 1959 2 Sheets-Sheet l ALEXANDER BOY/V m/v,

//VI/E/V 70/1 M cfbm f 0% ATTORNEYS.

March30, 1943. BOYNTQN 2,314,868

FLQWING DEVICE, TUBING, AND CASING FLOW ATTORNEYS.

Patented Mar. 30, 1943 umrao STATES FLOWING-DEVICE, ["UBING, AND CASING FLOW '13 Claims.

. My invention relates to flowing devices for "wells, "the :fiow: being-accomplished by the expansive: force of compressed air -or gas.

.Thepprincip'al object is tov provide means for actuating :the valves by "pressure --acting on -"a iarger areathan-that of the valves.

.Another. equallyrim'portant object is to providermeansTor preventing the valves 'fromopening iprematurely, due to 1v gas "breaking through the well liquid or due to slippagebi" the well liquid in the'ieduction' tube.

.Another :ob'j ect' is' to 'provide means for causing .iawellttoffiow'through theltubing from pro- ;gressively -lower levels :by pressure "fluid from within the casing admitted through devices 'Spacedat intervals inthe tubing and-by the employmentof identical means, to 'cause Ta well to 'fi'ow'by stages through'the casing 'by or gas pressure in the tubing.

"A further. object is to provide valves that will seat-and 'sealo'ff with :greater force and certainty than can be accomplished b'y 'valves now employed in the art.

Another object is to throttle the amount of pressure fluid "passing each valve at 'high pressure so that the valves andseats will not 'be abraded.

A further object .is to automaticallythrottle the pressure fluid admitted 'through each device according to theload to be lifted.

Two valves "are movably balancedhetween two springs .in the .path of the pressure "fluid emplayed :as the lifting force, eac'h valve being adapted to regulate the inflow "of pressure 'fluid. and finally to close on its seat and -cut on the in'fiowof pressure fiuid at apriedetermined "difference'be'tween the value of the pressure fluid and the load to he lifted by 'it.

In 'carrying "out this 'inventiomair -or 'gas 'hnder pressure in'the casing causes a column of well liquid to upstand in the tubing, or air or gas pressure 'in the tubing causes a column of we'll-liquid to upstand inthe casing. In either event, air or gas is discharged through the "devices. spaced at intervals in 'the'tubing, the larges't volume of air or gas being discharged into the upstanding column throughthe Widest open device which is the one nearest to the 'base "of the upstanding liquid column. The valves in the devices above the one "nearest to the base of the upstanding 'column are progressively proportion to the lightening pressure of the upstanding column at each higher deviceebove the base of the upstandingcolumn.

Tattain the 'foreg'o'ingobjects by mechanismil- Iustrated in the accompanying drawings, in

which-- a Fig. 1 Ban installation of the device installed in afwell.

Fig. 2-is mainly a longitudinal section of'the preferred embodiment-of the invention;

Fig. 3 is a cross-section nnthe lined-3; Fig-2.

Fig. l'is mainly a longitudinal sectionofa slightly modified form 'of the valve mechanism.

Fig. 5 is a cross-section on-the line -'5-5; Fig.--2.

Fig-6 is*a longitudinal section of -'a=mod-ifled iorm'of the invention.

Fig. 7 is mainly a longitudinal section'o'f an other modified form of'the valve construction.

Fig. "8 --is mainly -a --1ongitudir al section of v a further modified form of the valve construction.

Fig. 9' is' a cross-sectionon the line-9 9 Fig; 6.

Fig. 10 is across-sectionon the 'line'lll-aln; Fig. 6. v f

Similar reference character s-refer to sinner parts throughout the several views.

The nipple portion '3-of the device is adapted to-have threaded connection with the couplings 2a of the 'tubing string 2. These devices 'Within the casing tare spaced in the tubing at intervals which may vary from approximately .150. to 300 feet.

The anchor string 1, below the tubing 2, may be landed upon the bottom, of the well bore-9. The

intakeordischarge nipple 6, having lateral openings ta, admits the well liquid if the well is being flowed through the tubing; and-becomes the lower air or gas discharge from "the tubing if the well-is beingflowed through thecasingl The perforations H admit the contents of the producing formation Ill into the well casing. The pipe l2 may be employed to 1 admit-external gas under pressure into the well, or may he used to conve excess gas away from the well. The casing head 4, which 'may be-of any other cone ventional design, may be employed proximately above the ground surface 8 to effect a seal be tween-thecasing 4 and the tubing 2. V

The upper end of the tubing 2 may extend to a flow tank, if the well is being flowed through the tubing, or the flow line 5 may-extend to the nearer to their closed positions, due :to the fact 7 that the force tending to close all valves contactingthe upstanding column is the same, while the rorce resisting such closing diminishes in flow tank if the well is being-flowed through the casing.

-If the well is to be flowed through the tubing 2 and does not produce enough gas to flow it,

mechanism is resiliently supported between two coiled springs I3 and I4, installed under some compression.

The proximate ends of these springs engage upon packing rings 25 and 25 which rings are slidable within the bore 30 and over the upper projection of packing housings 26 and 26. The

bore 30 may have a diameter such as one to one.

and one-half inches. The springs I3 and I4 have their extreme ends engaged upon plug base 32 and lower end plug 29, respectively. These springs may be of equal force.

Both movable packings 24 and 24! are constantly under compression from the springs, and, on account of the sloping interior surfaces of the housings 26 and 26', these packings are constantly urged against the surface of the bore 30.

The upper valve'member I8 and the lower valve member I9 are held abutted together by the flanged outer extremities of upper valve retainer and lower valve retainer 2|, threadedly joined together as appears in Fig. 2. The U cups 22 and 22', which may be of leather or any other tough, yieldable substance, fit snugly over the upper tubular portion of the lower valve retainer 2|. These cups, which may be replaced by any other suitable form of packing or by metallic rings, are separated by the ring'23 and secured in position by the outer flanges of retainers 29 and2I.

The assembly of parts I8 to both inclusive which has a close sliding fit within the polished bore of chamber 30, will be referred to as the movable valve assembly.

The difference in pressures obtaining above and below the movable assembly will be referred to as the differential, which is the difierence between the value of the pressure fluid and the back pressure of the well liquid at any level in the upstanding column, caused by the pressure fluid.

.The opposed valve seating and unseating forces operating upon the movable assembly are equal, except the back pressure of the well liquid in the upstanding column which varies according to its place in that column.

The slot 311 in the partition wall between nipple 3 and shell 3a places the upper end of the movable valve assembly in open communication with the interior of the tubing, and theouter slot 3e places the lower end of the valve assembly in open communication with the annular space Ia. The movable valve assembly, resiliently supported between the coiled springs I3 and I4, has the central opening I 8b adapted to be closed by the valve I8a when it engages the seat I5a, or by the valve Illa when it engages the seat IBa. This assembly is a floatingbarrier between the inside of the tubing and the annular space Ia of the casing and, therefore, is always subject to be actuated by the pressure differential. The valve seats I51: and I6a limit the piston travel between the slots 3d and 3e.

The ports 20a and 2Ia and the annular spaces 20b and 2lb provide that pressure fluid will expand the U cups (or compress the packing if packing be employed instead of cups) on the side of the greatest pressure. The compressed packing 24 and 24' will sweep the wall of the bore 30 clean ahead of the cups or packing 22 and 22' as the valve assembly moves in either direction.

The governor enlargement I la is of slightly less diameter, such as 1 to 5 thousandths inch, than the smallest inside diameter of the opening I8b through the upper and lower valve members l8 and I9, these places of smallest diameter being proximate the upper and lower ends of these members. The central opening I8b through the valve members I8 and I9 enlarges from their outer ends toward their proximate ends where the enlargement Ila has greatest clearance within it, such as [15 to inch. This opening is the only communication between the inside of the tubing and the annular space Ia, except through the nipple 6 or through the bottom end of the tubing. The upper end of bore 30 is hermetically closed. The plug base 32 is closely received within the extremity of this bore and landed upon the slight internal annular shoulder 31. The gland ring 28,-

having an internal diameter slightly greater than that of the smaller end ofbase 32 and an external diameter slightly less than the diameter of the opening in the end of shell 3a above'the shoulder 3f, serves to compress the packing 33 by means of the threaded engagement between the plug 21 and the shell 3a.

The lower end plug 29 has threaded engagement within the lower end of the shell 3a. The upper sloping end 3b and lower sloping end 3b of the shell 3a serve to guide the device through irregularities in the casing. Central of the bore 30, the upper valve rod I5 and the lower valve rod I6 each has a threaded connection with the governor rod IT. .The valve IBa is adapted to seal off upon the seat I5a, and the valve I 9a is adapted to seal oif upon the seat Mia. The upper adjustment securing ring 39 has threaded engagement over the upper end of the rod I5 and engages upon the packing 3| within the upper end of the base 32. The lower adjustment securing ring 39' has threaded'engagement over the lower end of the rod l6 and is adapted to land upon an internal flange within the upper end of the plug 29.

The governor enlargement Ila may be longitudinally positioned relative to the valve assembly by means of the threaded connections at either end of the rods I5 and I6, as is apparent in Fig. 2, the slots I51), I 6b, 30a, and 30a being to receive tools in making such adjustments.

In all forms of the invention, the devices, preferably, should be spaced apart in the tubing at such distance that the well liquid between adjacent devices will weigh somewhat less per square inch than the pounds per square inch of diflerential required to close the valves. Otherwisev stated, the force of the springs I3 and I 4 should be such that the difierential per square inch required to close the valves in the devices willbe somewhat more than the weight of the well liquid exerted per square inch between adjacent devices. Such adjustment will cause the uppervalve to remain always open until the next lower valve has been uncovered by Well liquid.

The diiierential force required to close the valve in all forms of the invention may be, for example, 50 to pounds per square inch, This ordinarily will require the valves to be to 300 feet apart.

The value ofthe pressure fluid employed to flow the well, in all forms of the invention, prefplaced stably, :should be :at least twice .or .more than twice the value of the-(inferential :necessars to close the valves. Obviously, increasing the value of the gpressmte ifluid will. increase the rate of liquid flowin either direction and vice versa.

The'valves in all forms of the device are mor mallyopen by the balanced force of the opposed springs l3 and M on either side of the movable assembly, the valve closing movement in either direction :being caused by the pressure :fiuid on the opposite :side, which will :close either valve at :a predetermined idifierential.

.It will be understood that flow of well liquid tlnlough the eduction tube results from the expansion of the pressure fluid admitted into this liquid through the devices.

:Breceding the operation of flowing a well through the tubing by means of -.a construction such as that just described, it is assumed that the flow line 5 and-:thetubing 2 are both closed by valves, not shown, exteriorof the Well.

To rfiOW the well through the tubing a valve in the line I2 exterior of the well is opened to admit into the annularspace Ia compressed air or .gas of somewhat :greater value than the difierential required to close the valves in the devices, if the well does not produce enough gas to flow dt, then open the valve (notshown) in the tubing 2. This will oause the well liquid 'to be depressed in the casing to a level :assumed to be at ;A, and to :upstand in the tubing to a level in dicated at .B. All valves above the upstanding column in the tubing will be closed then by the greater pressure below the movable valve assembly than above it. The pressure will be greater below than above this assembly, because the ,pressure within the tubing will "be bled off lay-opening the valvein-the tubin'g. All valves in the devices then will be bpen opposite the upstanding column -of well liquid where the :pressure of this liquid, :plus the compression :force of spring t3 isigreaterthan'the pressure withinthe annular space to, The remaining valves will be closed.

The enlargement a being normally in the central position at the vplace of the greatest bypassing area through the central opening 48b as appears in 2, it is'evident that the greatest volume of pressure fluid will pass through the device and into the upstanding liquid column during the time of least difference in pressures above and below thesmovable valve :assembly. the -,difierential increases, "that "is. as the :pressure of the upstanding column within the tubinjg diminishes at any device, the valve lilia'will approach its seat 15a. In this :manner, the greatest volume of pressure fluid is discharged into the upstanding column by devices :nearest the base of the :liquidcolumn and the volume of such fluid is automatically dim nished as the liquid load diminisheauue to the liquid being dischargedlfrom the well.

The valves in the upper devices will "close in progression as the liquid level is lowered in the casing and lower devices are uncovered by the receding liquid. Each -device is uncovered in the open position of its valve, because of the slight differential there; while the upper valves close, due to'increasing difiereutial there as the upstanding column of well liquid grows lighter above them.

New, "to flow "the well through the casing, admit into the tubing 2 compressed a'ir or gas of somewhat greater value than that required to close the valves in the devices, and then open the valve in the rfiow line 5. will cause the well liquidto be depressed :in the tubing to a level indicated at C and to upstand in the casing to a level indicated 'at D. All valves :above the upstanding :colu-m-n in the casing will be closed then by the greater pressure above the movable valve assembly than below it. At all levels above the upstanding liquid column, the pressure will he greater above than below this assembly, because the pressure within the annular space 'la will he bled off by opening the valve in flow line 5.

.All valves will be open within the "upstanding column of well liquid where the-pressure of the liquid, plus the compression force of the spring Myi-s greater than the pressure within the tubmg.

From the foregoing, it will be-observed that the pressure fluid of proper value within either the casing or the tubing will cause the well to flow through the other conduit by means oi -these devices.

The valve action of the devices is similar Whether the well is flowed through the tubing or through'the casing.

The enlargement Ila being normally in the central position at the place of greatest lay-passing area through the opening 181), as appears in Fig. 2, it isiev'ident that the greatest volume -of pressure fluid will pass through the device and into the upstanding liquid column in the casing during the time :of least difierence :in pressure above and below the movablevalve assembly. As the differential increases, that is, as the pressure of the upstanding column in the annular space lxa of the "casing diminishes, the valve Isa will approach its seat Ilia. In this manner, 't-hegreatest volume of pressure fluid is discharged'intotheupstanding column :in the casing by the device nearest the base of the column, and the volume of such fluid is automatically :diminished :as the liquid load diminishes, due 1130 the liquid being discharged iromthe well,

Flowing through the tubing ordinarily will re suit .in more economical gas-oil ratios. Generally speaking, only wells of "great production should be flowed through the casing, but means to clean out wells by occasionally :fiowing them through the casing is an operating convenience amply justifying the installation of devices that can be employed to flow through either the tubing orfthe-casing.

If the production :of the "well is to be obtained by flowing through "the tubing, better results will be obtained by cenlarguig the tubing toward the 1 top of the well, 'a'srillustrated in Fig. 1; but if the casing flow is to be employed, the tubing may be smaller and, preferably, :all of one size.

iIn Fig. 4 the construction is the same as in Fig. 2, except that between'theupper'valve mem-. ber 34 and thelower valve member 35, a govern'or ring 36 is interposed. These three mem'bersbeing held in place "by the flanged extremities of valve retainers 2e "and 2 i, provide a central passage for pressures'fiuid, similar to the showingzin Fig.2. The-enlargement llainFig. 4 is normallv :oppusite them'iddle of the movable assembly, through which it .h'a's slight clearance within the central portion of the central opening 34a through the member $5. It will be notedthat the greatest passage way around the enlargement flu is approximately midway of the valve travel in either direction. This construction will admit "through the opening 34a, extending through the inovable assembly, only :a vrelatively small quantity of pressure'fiuid into the upstanding column at slight differentials, and gradually will increase the amount of pressure fluid so admitted to the maximum amount approximately midway between the least and the greatest differentials during which the valves will remain open.

' It will be observed in Figs. 2 and 4 that the enlargements I la and Ila, respectively, will be in the throat or smallest opening through one valve While the other valve is seating. This construction prevents the seating valve (whichever one it may be) from being out by abrasive substances just before it seats, this being the time when most cutting would occur, except for the throttling action of enlargement lla or H0. in the throat of the other valve.

- For the valve assembly in Fig. 4, the size of the largest passage around the enlargement Ila through the movable valve assembly, ordinarily may vary between the equivalent of A to inch diameter circular openings, depending upon the size of the eduction tube, physical properties of the liquid to be lifted, and other well conditions. In the throttling operation, the size of the smallest passage-Way may be, for example, ten per cent or less, than that of the greatest passageway.

The governor enlargement To may have a straight portion adapted to have slight clearance, such as .001 inch, with the central opening 34a at its three places of smallest diameter. This straight portion will prevent the fluctuating pressures in the eduction tube from instantly changing the size of the opening through the throats at the extreme ends of the opening 34a. The enlargement Ila in Fig. 2 may be similarly constructed for the same purpose.

In the modified form, Fig. 6, parts 45 to 5|, both inclusive, will be referred to as the movable valve assembly. The nipple portion 31, and the shell'3la may be cast integrally, the inner slot 31d communicating between the nipple and the shell and the outer slot 31:; communicating between the shell and the annular space la, within the well casing. The shell bore 310 has a smooth finished surface between the slots 31d and 31a. The movable valve assembly has a close sliding fit within this bore, the valves being adapted to seat and thus confine the piston travel between the slots. The sloping shell ends 311) and 31b serve as guides through the well casing.

The upper governor pin base plate 4| lands upon the upper small iternal annular shoulder 31 The packing 40 is impinged between the upper surface of the plate 4| and gland ring 39 bythe top plug 38. The upper end of the bore 310 is thus hermetically closed. The lower governor pin base plate 4| lands upon the lower small internal annular'shoulder 31f and is secured thereby the bottom plug 38'.

The coiled spring 43, installed under some com-- pression, is engaged between th upper plate 4| and the upper packing gland ring 50 of the mov able assembly. The spring 44, similar to the spring 43 and likewise installed under similar compression, is engaged between the lower plate 4| and the lower packing gland ring 56.

Th upper pin base 42 has threaded connection with the plate 4 and the lower pin base 42 has threaded connection with the plate 4|. The tapered pin 42a depends centrally of the opening through the upper valve member 45, and the tapered pin 42a upstands centrally of the opening through the lower valve member 46. The greatest clearance between each of these pins and the member into which it extends, may vary from the equivalent of a circular opening A; to inch diameter when the valves are open, as shown in Fig. 6, to a clearance of 1 to 5 thousandths inch when the valves are closed. The valve 45'- -is adapted to engage upon the valve seat 42b and the valve 46 is adapted to engage upon the valve seat 42b.

.The governor pins 42a and 42a may be arcu-' ately tapered as shown and preferably each should have a straight portion a having a close valve-like fit within the mating valve members, the straight portion a being for the purpose of preventing the valves from fluttering due to the frequent diiference of high and low pressure areas in the flow tubing.

The continuous central opening 45ethrough the movable assembly communicates with the em larged openings within the extremities of the valve members 45 and 46. These openings constitute the only path for pressure fluid to enter the upstanding column of well liquid during the flowing operation. 7

The upper valve member 45 and the upper valve sheath 45a are made separately for manufacturing convenience, pressed together and secured by the weld 45d. The upper valve flange 4517 has pressure fluid openings 450. The lower valve member 46, for manufacturing convenience,

is pressed into the lower valve sheath 46a andsecured there by the weld 46d. The lower valve flange 462), having pressure fluid openings 46c, and the upper flange 45b, confine between thm the U cups 4'! and 41, these cups being separated by the ring 41a. The upper movable packing'48 is confined within the annular'housing 49 by the gland ring 5!), slidable over the upper member 49,

and contacting the upper spring 43. The lower movable packing 48' is confined within'the annular housing 49' by the gland ring 50, slidable over the upper member 49, and contacting the lower spring 44. The upper U cup 41 is adapted to be expanded and urged against the wall of the bore 310 by pressure fluid acting from above through the openings 45c and the annular space 5|. Likewise, the lower U cup 41 is adapted to be expanded and urged against the wall of the bore 310 by pressure fluid acting from below through the openings 46c and the annular space 5|. The inclined portions of the packing housings 49 and 49 are'adapted to urge th pack-' ings 48 and 48 against the wall of the bore 31c.

The movable assembly is secured together by the threaded connection between the upper valve member 45 and the lower valve sheath 46a, as appearsin Fig. 6.

Fig. 7 illustrates a modification which is the same as shown in Fig; 6, except for the valve mechanism and portions of other parts omitted between the lines a-b and ccl.

The movable assembly, as illustrated and described ln connection with Fig. 6, will be assumed tobe installed within the central broken out portion of Fig. 7.

The upper valve seat member 52, having the valve seat 52a adapted to engagethe valve 53a, has threaded connection within the plate 4|. The lower valve seat member 52', having the valve seat 52a. adapted to engage the valve 53a has threaded engagement within the plate 4|, said valves and valve seats being similar and operating in apposition to each other. The extreme-ends of valve members 53 and 53' have tapered central openings, the diameters of which enlarge outwardly of the valves 53a and 53a, re-

spectively. These openings communicate with the central passage 45c and constitute the only path through the movable assemblyior pressure fluid to pass into the upstanding column. The clearance between the shell ofmember 53 and the-member- 52 and the clearance between the shell-of member 53' and the member EZ may be th -equivalent of a circular opening /3" to s diameter when the valves are open, as in Fig. '1. construction automatically throttles the amount of pressure-fluid whichmay pass-through the device as the differential increases by the diminishing clearance between the male and female. members of the valves asthey close.

A straight portion 1) of the valve members 53 and 53 may have a close slidevalve fit over the end of the members 52 and 52- in order to prevent sudden changes of pressures within the eduction tube from causing the valve to waver chatter.

Fig. 8 illustrates a-furt'hermodification but is the same as that shown in Fig. 7, except for slight changes in the valve construction. The movable assembly, except as to the valves,- will be understood to be the same as that shown and described for. ither Fig. 2 or Fig. 6.

Theupper valve seat member 54 hasa seat 51m adapted to engage the valve 550. of the upper valve member 55. The lower valve seat member 54-" is similar to the upper member 56-, and has within it a seat 54a similar to the seat 5411 which engages the valve 55a in apposition to the valve 55a. The upper governor pin member 56; having threaded engagement within the member'54, has a pin 56a adapted to be closely received within the central opening 55b through the member 55 as the valve seats. In apposition, the lower gov-- ernor pin member 55" has a similar pin 56a" re-' ceived within the other valve 55a, similar tothe valve 55a.

It will be understood that the central opening 55b extends through the movable assembly, the central portion of which is broken away, as in Fig. '7.

The central opening within the member preferably, is arcua-tely tapered, the normal clearance between the members 5 3 and 55,- whenthe valve is open, being the equivalent of a air-- cular opening of A; to T' e inch diameter. The clearance between these members may be one to: five-thousandths inch when the valve is closed. A similar relation exists between the lower valve member 55' and its mating member 54'.

The pins 56a and 56a prevent sudden changes of pressure in the eduction tube from suddenly forcing the valves open during high differentials and; also protect the valve seats from becoming abraded by sand or other abrasive substances frequently present in the pressure fluid.

The installation and operation is the same as heretofore described for the preceding embodiments.

After any cessation of the flowing operation through the tubing, it is apparent that the movable assembly will be forced upon its nether valve by the weight of well liquid in the tubing above it if a check valve be provided in the tubing anywhere between the nipple and thelowest flowing device.

The diameter of the movable valve assembly being many times greater than the diameter of the valves, it is evident that much greater force will be imparted to the valves in their movements and upon their seats than would result from applying the valve actuating force to the same area as that-of the valve, as is-the=- present practice iii-devicesemployed for a similar purpose;

The installation and operation of-' the devices is essentially the same in al1 formsof the invention.

Comparatively-low g-as-liquid ratios result from thelow starting pressures and themeter-ed fiow ofpressure fluidin combination with the-securely" seating valves operated? by abalanced piston,

asabove set out. Y 7

It isobvious that many mechanical changes, substitutions and adaptations maybe-made-within the scope and purpose of this invention as comprehended by the stated objects and appended claims, and I reserve the=rightt0imake such changes, substitutions and adaptations.

What isclaimed:

1. A deviceofthe class described comprising-a valvebod'y havinga passageway between the exterior and the interior thereof, a pair of spaced aligned valve seats in said passagewayyan orificed piston movable in the passageway and adaptedto maintain sealed engagement with the walls thereof, the orifice in said piston including outwardly" facing valve seating" surfaces; and means resiliently urging said piston to a position intermediate" said valve sea-ts; there being spaced openings at opposite sides of said piston-and leading respectively from the passageway tothe exterior and interior of thevalve body sothat pressure fluid is metered in its flow throughthe openings, passageway and piston; and a movable packing at at least-one endof said orificedpiston engageable by said means and urged intosealing engagement with the walls of the passageway.

2. A device of the class described comprisinga valve body having a passageway between theexteri'or and the interior thereof, opposed valve" seatsi'n ali'gnmentwithin said passageway; a-mov-- able valve assembly within the passageway, said assembly including a piston having an axialpas sage in alignment with the valvesea-ts; outwardly facing valve seating surfaces on the piston; andmeansfor metering the-volume of fluid flowing through the piston when the valve seats and seating surfaces are: out of engagement, said passagewayincludingspaced ports-at opposite sides of said assembly leading respectively tothe -interior and exterior of the valve'body;

A well} flowing device comprisinga val ve havinga body with a passageway afiording'communication from the exterior tothe-interiorof' the body, a valve assembly movable axially of and sealab'ly engaging the walls of the passage way, said va-lveassembly having a passage there through, outwardly facing valve seating surfaces insaid passage, spaced opposed valve seats in. alignment with said valve seating surfaces, andmeans resiliently urging said: assembly to a 'pos-i-' tion: intermediate the valve seats, said passageway including spaced ports at opposite sides of said assembly leading respectively to the interior and exterior of the valve body.

4. A well flowing device comprising a valve having a body with a passageway from the exterior to the interior thereof, a valve member movable axially of the passageway, said member having an opening therethrough and converging toward the ends of the member, outwardly facing valve seating surfaces at the ends of said opening, a valve rod passing through the opening, opposed valve seats on said rod adapted to be engaged by said valve seating surfaces, and an enlargement on the rod within the opening for governing flow of fluid therethrough.

5. A well flowing device comprising a body having a passageway from the interior to the exterior thereof, a valve assembly movable axially of the passageway, said assembly having an opening therethrough, a tubular valve member fixed in said opening, enlargements in the ends of the bore in said member, the walls of said enlargements including an outwardly facing valve seating surface, and oppositely facing valve seat members in alignment with said valve member and adapted to enter the enlargements and meter the flow of fluid through the tubular valve memher.

6. A well flowing device comprising a body having a passage from the interior to the exterior thereof, a valve assembly movable axially of the passageway, means resiliently holding said assembly at a predetermined position withinthe passageway, said assembly having an opening axially of the passageway, a tubular valve member fixed in said opening, enlargementsin the ends of the bore insaid member, the walls of said enlargement including an outwardly facing valve seating surface, and oppositely facing valve seat members in alignment with the valve member and; adapted to enter said enlargements and meter the flowoffluid through the tubular valve member. l

7. A well flowingdevice comprising a body having a passage from the interior to the exterior thereof, a valve assembly movable axially of the passageway and sealably engaging the walls thereof, said assembly having an opening therethrough, said opening being enlarged at its ends, an outwardly facing valve seating surface at each end of the opening, and a pair of opposed valve seat memberson opposite sides of the assembly and in alignment ,with said opening, said, membersbeing adapted to enter the ends of the openingto meter the flow of fluid through the passage ay- 1. s

8f .fA, we l lowing device comprising a body having a passage from the interior to theex terior thereof, a valve assembly movable axially of the passageway and sealably engaging the walls thereof, said assemblyhaving an axial opening therethrough and the inlet and outlet to and from said passag way being at opposite sides of said assembly, outwardly facing valve seating surfaces in said opening, and opposed valve seat members in alignment valve seat members and opening being relatively contoured so that liquid flowing through the opening is meteredby relative telescopic movemerit thereof as the valve seating surface approaches the valve seat.

, 9, A well flowing device compri ing a valve having a body with a passageway from the exterior to the interior thereof, an annular piston withi'nsaid passageway, a stationary rod passing with said opening, said through said piston, a governor enlargement on said rod within the opening in the piston, and resilient means normally holding the piston in a. predetermined position relative to the enlargement, the opening within said piston being con. toured so that fluid is variably metered through thepassageway by differential fluid pressures between the interior and exterior of the valve body.

10. A well flowing device comprising a valve having a body with a passageway from the exterior to the interior thereof, an annular piston within said passageway, a stationary rod passing through said piston, a governor enlargementon said rod within the opening in the piston, and resilient means normally holding the piston in a predetermined position relative to the enlargemerit,- the opening centrally within said piston having .a slight clearance with said enlargement and successively converging and diverging outwardly therefrom whereby fluid is metered through the passageway by diiferential fluid pres sure between the interior and exterior of the valve body. I

11. A well flowing device comprising a valve having a body with a passageway from the exterior to the interior thereof, an annular piston within said passageway, a stationary rod passing through said piston, a governor enlargement on said rod within the opening in the piston, valves on the ends of said piston, spaced valve seats on said rod adapted to be engaged by said valves, the opening within said piston being contoured so that fluid is variably metered through the passageway by differential fluid pressures between the interior and exterior of the valve body.

12. A Well flowing device comprising a valve having a body with a passageway from the exterior to the interior thereof, an annular piston within said passageway, the opening within said piston converging toward the ends of the piston, a stationary rod passing through said piston, a governor enlargement on said rod within the opening inthe piston, and resilient means normally holding the piston in a predetermined position relative to theenlargement.

13. A well flowing device comprising a valve having a body with a passageway from the exterior to the interior thereof, an annular piston within said passageway, the opening within said piston converging toward the ends of the piston, valves on the ends of said piston, a stationary rod passing through said piston, spaced valve seats on said rod adapted to be engaged by said valves, and resilient means normally holding the piston intermediate said valve seats, whereby fluid is variably metered between the exterior and the interior of the valve body and the passageway is closed when the exceeds a predetermined value,

ALEXANDER BOYNTON.

pressure diiferential 

